1. Field of the Invention
The present invention generally relates to a method for forming a gold plating electrode, a substrate based on the gold plating electrode forming method, and a wire bonding method utilizing the gold plating electrode forming method.
2. Prior Art
According to conventional technologies, it has been well known that gold plating is used to form an electrode on a glass epoxy substrate and thus formed electrode is electrically connect with a chip through bonding of a wire. In this case, gold plating must provide sufficient bondability, such as bonding strength, to a ball formed at a distal end of the wire.
From numerous experiences, it has been conventionally believed that the thickness of a gold layer formed by the gold plating needs to be as thick as 300 nanometer or more. To this end, it was usual to utilize the electro plating or electroless reduction plating to form a gold layer being sufficiently thick.
However, as well known to artisans, it takes an extremely long time until a growing gold layer reaches a required thickness when the gold layer is formed by the electro plating or electroless substitution plating, and the manufacturing cost must be expensive.